P1147: FEASIBILITY AND OUTCOME AFTER DOSE REDUCTION OF IMMUNOCHEMOTHERAPY IN YOUNG ADULTS WITH BURKITT LYMPHOMA AND LEUKEMIA. RESULTS OF THE BURKIMAB14 TRIAL
Authors: Josep Maria Ribera, Mireia Morgades, Olga García-Calduch, Maialen Sirvent, Buenaventura Buendía Ureña, Marta Cervera, Hugo Luzardo, Jesus Hernández Rivas, Marta Sitges Arriaga, Irene Garcia Cadenas, Pablo Abrisquet Acosta, Pau Montesinos, Mariana Bastos Oreiro, María-Paz Queipo de Llano, Pilar Bravo, Anna Torrent, Maria Pilar Herrera Puente, Antonio Garcia-Guiñon, Ferran Vall-Llovera Calmet, Josefina Serrano, Maria J Terol, Juan Miguel Bergua Burgues, Ana García-Noblejas, Cristina Barrenetxea, Laura Llorente, Daniel García-Belmonte, Eva Gimeno, Antonia Cladera, Santiago Mercadal Vilchez, Juan Manuel Sancho
Journal: HemaSphere (2023)

Topic: 19. Aggressive Non-Hodgkin lymphoma - Clinical Background: High dose-intensive or infusional low-dose immunochemotherapy is a very effective treatment for Burkitt lymphoma (BL) irrespective of human immunodeficiency virus (HIV) infection. However, toxicities of these regimens are relevant. Dose reduction of chemotherapy after complete metabolic response (CMR) achievement could reduce toxicity without impact on outcome. Aims: The objective of the BURKIMAB14 trial (NCT05049473) was to evaluate the feasibility and outcome of young adults with BL after reduction of chemotherapy after CMR and to compare with those of similar patients (pts) included in the former BURKIMAB08 trial (Ribera JM, et al. Cancer. 2013; 119:1660-8), in which there was no dose reduction after CMR. Methods: Adult pts aged 18-55 yrs. were treated with Rituximab and intensive chemotherapy blocks according to the stage. Pts with localized stage (I, II non-bulky) received 4 cycles (A, B, C and A) and pts in advanced stage (II with bulky disease or III-IV) received 6 cycles (A, B, C, A, B, C). CNS prophylaxis consisted of TIT (methotrexate, cytarabine and hydrocortisone) administered in the pre-phase and twice in each cycle A and B, for a total of 9 doses in all pts. After completion of chemotherapy, CMR pts in advanced stages received two additional doses of rituximab. Compared with the BURKIMAB08 trial, in the BURKIMAB14 trial, IV methotrexate for cycles A, B and C was reduced 33% (1500 mg/m2 to 1000 mg/m2), iphosphamide was reduced 28% in cycle A (800 mg/m2 to 500 mg/m2) and cytarabine was reduced 25% in cycle C (2000 mg/m2 to 1500 mg/m2). Results: Sixty-eight pts aged 18-55 yrs. (median 39, 55 males) were included in the trial. Stage was localized in 21 pts (31%) and advanced in 47 (69%). 17 pts (25%) had HIV infection. CNS was involved in 10 pts (15%). Burkitt’s leukemia (>20% Burkitt cells in bone marrow) was observed in 19 pts (28%). Bulky mass (>10 cm) was present in 24/65 pts (37%). BL-IPI risk distribution (evaluable in 66 pts): low 16 (24%), intermediate 21 (32%) and high 29 (44%). Three patients discontinued the study before response evaluation, early death occurred in 1, resistance in 4 (6%) and CMR was attained in 60 (88%). 3 pts dead in remission and 5 relapsed. With a median follow-up (range) of 3.61 (0.1-7.42) yrs., the 4-yr OS probability was 82% (95%CI, 70% - 90%). Compared with the BURKIMAB08 trial no differences were observed in response to therapy and survival (4-yr OS in BURKIMAB08 trial 72% [95%CI, 61% - 80%], Figure 1). Regarding toxicity there was a significant reduction in the median duration of thrombocytopenia (6 days vs. 3 days, p=0.013), in the number of grade 3-4 infections (74/87 [85%] vs. 45/65 [69%], p= 0.019), and in the deaths by infection (12 [14%] vs. 2 [3%], p=0.019). Conclusion: The results of BURKIMAB14 in young adults are similar to those of other dose-intensive immunochemotherapy trials. Dose reduction of chemotherapy after CMR achievement decreased toxicity and did not have impact on outcome. Funding: Supported in part by the grant 2021 SGR 00771, AGAUR, Generalitat de Catalunya, Spain. Figure 1. Overall survival of pts in the BURKIMAB14 and BURKIMAB08 trials.Keywords: Treatment, Burkitt’s lymphoma, Young adult, Reduced intensity